Differential diagnosis of Crohn’s disease and intestinal tuberculosis based on ATR-FTIR spectroscopy combined with machine learning

BACKGROUND Crohn’s disease(CD)is often misdiagnosed as intestinal tuberculosis(ITB).However,the treatment and prognosis of these two diseases are dramatically different.Therefore,it is important to develop a method to identify CD and ITB with high accuracy,specificity,and speed.AIM To develop a method to identify CD and ITB with high accuracy,specificity,and speed.METHODS A total of 72 paraffin wax-embedded tissue sections were pathologically and clinically diagnosed as CD or ITB.Paraffin wax-embedded tissue sections were attached to a metal coating and measured using attenuated total reflectance fourier transform infrared spectroscopy at mid-infrared wavelengths combined with XGBoost for differential diagnosis.RESULTS The results showed that the paraffin wax-embedded specimens of CD and ITB were significantly different in their spectral signals at 1074 cm^(-1) and 1234 cm^(-1) bands,and the differential diagnosis model based on spectral characteristics combined with machine learning showed accuracy,specificity,and sensitivity of 91.84%,92.59%,and 90.90%,respectively,for the differential diagnosis of CD and ITB.CONCLUSION Information on the mid-infrared region can reveal the different histological components of CD and ITB at the molecular level,and spectral analysis combined with machine learning to establish a diagnostic model is expected to become a new method for the differential diagnosis of CD and ITB.

Intestinal Behçet's disease: A review of clinical diagnosis and treatment

Behçet's disease(BD)is a chronic inflammatory disorder prone to frequent re-currences,with a high predilection for intestinal involvement.However,the ef-ficacy and long-term effects of surgical treatment for intestinal BD are unknown.In the current issue of World J Gastrointest Surg,Park et al conducted a retrospec-tive analysis of 31 patients with intestinal BD who received surgical treatment.They found that elevated C-reactive protein levels and emergency surgery were poor prognostic factors for postoperative recurrence,emphasizing the adverse impact of severe inflammation on the prognosis of patients with intestinal BD.This work has clinical significance for evaluating the postoperative condition of intestinal BD.The editorial attempts to summarize the clinical diagnosis and treatment of intestinal BD,focusing on the impact of adverse factors on surgical outcomes.We hope this review will facilitate more precise postoperative management of patients with intestinal BD by clinicians.

Computed tomography-based radiomics combined with machine learning allows differentiation between primary intestinal lymphoma and Crohn's disease

BACKGROUND Due to similar clinical manifestations and imaging signs,differential diagnosis of primary intestinal lymphoma(PIL)and Crohn's disease(CD)is a challenge in clinical practice.AIM To investigate the ability of radiomics combined with machine learning methods to differentiate PIL from CD.METHODS We collected contrast-enhanced computed tomography(CECT)and clinical data from 120 patients form center 1.A total of 944 features were extracted singlephase images of CECT scans.Using the last absolute shrinkage and selection operator model,the best predictive radiographic features and clinical indications were screened.Data from 54 patients were collected at center 2 as an external validation set to verify the robustness of the model.The area under the receiver operating characteristic curve,accuracy,sensitivity and specificity were used for evaluation.RESULTS A total of five machine learning models were built to distinguish PIL from CD.Based on the results from the test group,most models performed well with a large area under the curve(AUC)(>0.850)and high accuracy(>0.900).The combined clinical and radiomics model(AUC=1.000,accuracy=1.000)was the best model among all models.CONCLUSION Based on machine learning,a model combining clinical data with radiologic features was constructed that can effectively differentiate PIL from CD.

Breath test for differential diagnosis between small intestinal bacterial overgrowth and irritable bowel disease:An observation on non-absorbable antibiotics

AIM： To estimate the prevalence of small intestine bacterial overgrowth （SIBO） among patients with an earlier diagnosis of irritable bowel disease （IBS） in our geographical area, and to collect information on the use of locally acting non-absorbable antibiotics in the management of SIBO. METHODS： A non-interventional study was conducted in 73 consecutive patients with a symptom-based diagnosis.. RESULTS： When the patients underwent a ＂breath test＂, 33 （45.2%） showed the presence of a SIBO. Arcer treatment with rifaximin 1200 mg/d for seven days in 32 patients, 19 （59.4%） showed a negative ＂breath test＂ one week later as well as a significant reduction of symptoms, thus confirming the relationship between SIBO and many of the symptoms claimed by patients. In the other 13 patients, ＂breath test＂ remained positive, and a further cycle of treatment with ciprofloxacin 500 mg/d was given for 7 additional days, resulting in a negative ＂breath test＂ in one patient only. CONCLUSION： （1） about half of the patients with a symptomatic diagnosis of IBS have actually SIBO, which is responsible for most of the symptoms attributed to IBS; （2） only a ＂breath test＂ with lactulose （or with glucose in subjects with an intolerance to lactose） can provide a differential diagnosis between IBS and SIBO, with almost identical symptoms; and （3） the use of non-absorbable antibiotics may be useful to reduce the degree of SIBO and related symptoms; it must be accompanied, however, by the correction of the wrong alimentary habits underlying SIBO.

Radiological diagnosis of inflammatory ulcerative diseases of small bowel

AIMS To analyze the radiological features of the ul- cerative diseases of the small bowel. METHODS Thirty-five patients (20 men,15 women) with inflammatory ulcerative bowel diseases were stud- ied radiographically (barium meal and/or double con- trast study),including:11 cases of tuberculosis,13 Crohn disease,7 bowel Behcet disease,2 simple ulcer and 2 ischemic bowel disease. Diagnosis was estab- lished pathologically in 33 cases and by clinical obser- vation after therapy in 2 cases. RESULTS The lesions were located in ileum,in 9 of 11 cases of TB;in 10 of 13 cases of Crohn disease;in 5 of 7 cases of bowel Behcet disease;in 1 of 2 cases of simple ulcer and in 2 cases of ischemic bowel disease. Ulceration was always present with variable appearances. Longitudinal ulcers,and fissures were noted in Crohn disease only. There were 5 cases of large and deep ulcer and 3 occurred in bowel Behcet disease,10 of 13 cases of superficial and irregular ul- cers were tuberculous,2 cases of transverse ulcer were also tuberculous. CONCLUSIONS The morphologic appearances of the ulcer,surrounding mucosal alterations and bowel deformation were the basis for the radiologic diagnosis. Correct diagnosis was dependent on optimal X-ray ex- amination technique and proper interpretation of the morphologic changes.

Small intestinal angiosarcoma on clinical presentation, diagnosis, management and prognosis: A case report and review of the literature

BACKGROUND Angiosarcoma is a highly malignant soft-tissue sarcoma derived from vascular endothelial cells that mainly occurs in the skin and subcutaneous tissues.Smallintestinal angiosarcomas are rare,and the prognosis is poor.CASE SUMMARY We reported a case of primary multifocal ileal angiosarcoma and analyze previously reported cases to improve our understanding of small intestinal angiosarcoma.Small intestinal angiosarcoma is more common in elderly and male patients.Gastrointestinal bleeding,anemia,abdominal pain,weakness,and weight loss were the common symptoms.CD31,CD34,factor VIII-related antigen,ETS-related gene,friend leukemia integration 1,and von Willebrand factor are valuable immunohistochemical markers for the diagnosis of small-intestinal angiosarcoma.Small-intestinal angiosarcoma most commonly occurs in the jejunum,followed by the ileum and duodenum.Radiation and toxicant exposure are risk factors for angiosarcoma.After a definite diagnosis,the mean and median survival time was 8 mo and 3 mo,respectively.Kaplan-Meier survival analysis showed that age,infiltration depth,chemotherapy,and the number of small intestinal segments invaded by tumor lesions were prognostic factors for small intestinal angiosarcoma.Multivariate Cox regression analysis showed that chemotherapy and surgery significantly improved patient prognosis.CONCLUSION Angiosarcoma should be considered for unexplained melena and abdominal pain,especially in older men and patients with a history of radiation exposure.Prompt treatment,including surgery and adjuvant chemotherapy,is essential to prolonging patient survival.

Gastrointestinal motility and absorptive disorders in patients with inflammatory bowel diseases: Prevalence, diagnosis and treatment

Inflammatory bowel diseases(IBD),Crohns disease and ulcerative colitis,are chronic conditions associated with high morbidity and healthcare costs.The natural history of IBD is variable and marked by alternating periods of flare and remission.Even though the use of newer therapeutic targets has been associated with higher rates of mucosal healing,a great proportion of IBD patients remain symptomatic despite effective control of inflammation.These symptoms may include but not limited to abdominal pain,dyspepsia,diarrhea,urgency,fecal incontinence,constipation or bloating.In this setting,commonly there is an overlap with gastrointestinal(GI)motility and absorptive disorders.Early recognition of these conditions greatly improves patient care and may decrease the risk of mistreatment.Therefore,in this review we describe the prevalence,diagnosis and treatment of GI motility and absorptive disorders that commonly affect patients with IBD.

Potential model for differential diagnosis between Crohn's disease and primary intestinal lymphoma

AIM To evaluate the usefulness of different parameters to differentiate Crohn's disease(CD) from primary intestinal lymphoma(PIL).METHODS The medical records of 85 patients with CD and 56 patients with PIL were reviewed retrospectively. Demographic, clinical, laboratory, endoscopic, and computed tomographic enterography(CTE) parameters were collected. The univariate value of each parameter was analyzed. A differentiation model was established by pooling all the valuable parameters. Diagnostic efficacy was analyzed, and a receiver operating characteristic(ROC) curve was plotted.RESULTS The demographic and clinical parameters that showed significant values for differentiating CD from PIL included age of onset, symptom duration, presence of diarrhea, abdominal mass, and perianal lesions(P < 0.05). Elevated lactate dehydrogenase and serum β2-microglobulin levels suggested a PIL diagnosis(P < 0.05). The endoscopic parameters that showed significant values for differentiating CD from PIL included multiple-site lesions, longitudinal ulcer, irregular ulcer,and intraluminal proliferative mass(P < 0.05). The CTE parameters that were useful in the identification of the two conditions included involvement of ≤ 3 segments, circular thickening of the bowel wall, wall thickness > 8 mm, aneurysmal dilation, stricture with proximal dilation, "comb sign", mass showing the "sandwich sign", and intussusceptions(P < 0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the differentiation model were 91.8%, 96.4%, 93.6%, 97.5%, and 88.5%, respectively. The cutoff value was 0.5. The area under the ROC curve was 0.989.CONCLUSION The differentiation model that integrated the various parameters together may yield a high diagnostic efficacy in the differential diagnosis between CD and PIL.

OMOM capsule endoscopy in diagnosis of small bowel disease

Objective： To assess the diagnostic efficiency of OMOM capsule endoscopy （CE） in a group of patients with different indications. Methods： Data from 89 consecutive patients （49 males, 40 females） with suspected small bowel disease who underwent OMOM CE （Jinshan Science and Technology Company, review. The patients＇ indications of the disease consisted of the Chongqing, China） examination were obtained by retrospective following： obscure gastrointestinal bleeding （OGIB）, abdominal pain or diarrhea, partial intestinal obstruction, suspected inflammatory bowel disease, tumor of unknown origin, hypoproteinemia, constipation, weight loss, and elevated tumor markers. Results： CE failed in one patient. Visualization of the entire small bowel was achieved in 75.0%. Capsules were naturally excreted by all patients. The detection rate of abnormalities was 70.5% for patients with suspected small bowel disease, and the diagnostic yield for patients with OGIB was higher than that for patients with abdominal pain or diarrhea （85.7% vs 53.3%, P〈0.005）. Angiodysplasia was the most common small bowel finding. Active bleeding sites were noted in the small intestine in 11 cases. Conclusion： OMOM CE is a useful diagnostic tool for the diagnosis of variably suspected small bowel disease, whose diagnostic efficiency is similar to that of the Pillcam SB （small bowel） CE （Given Imaging, Yoqneam, Israel）.

Small intestine contrast ultrasonography vs computed tomography enteroclysis for assessing ileal Crohn's disease

AIM:To compare computed tomography enteroclysis(CTE) vs small intestine contrast ultrasonography(SICUS) for assessing small bowel lesions in Crohn's disease(CD),when using surgical pathology as gold standard.METHODS:From January 2007 to July 2008,15 eligible patients undergoing elective resection of the distal ileum and coecum(or right colon) were prospectively enrolled.All patients were under follow-up.The study population included 6 males and 9 females,with a median age of 44 years(range:18-80 years).Inclusion criteria:(1) certain diagnosis of small bowel requiring elective ileo-colonic resection;(2) age between 18-80 years;(3) elective surgery in our Surgical Unit;and(4) written informed consent.SICUS and CTE were performed ≤ 3 mo before surgery,followed by surgical pathology.The following small bowel lesions were blindly reported by one sonologist,radiologist,surgeon and histolopathologist:disease site,extent,strictures,abscesses,fistulae,small bowel dilation.Comparison between findings at SICUS,CTE,surgical specimens and histological examination was made by assessing the specificity,sensitivity and accuracy of each technique,when using surgical findings as gold standard.RESULTS:Among the 15 patients enrolled,CTE was not feasible in 2 patients,due to urgent surgery in one patients and to low compliance in the second patient,refusing to perform CTE due to the discomfort related to the naso-jejunal tube.The analysis for comparing CTE vs SICUS findings was therefore performed in 13 out of the 15 CD patients enrolled.Differently from CTE,SICUS was feasible in all the 15 patients enrolled.No complications were observed when using SICUS or CTE.Surgical pathology findings in the tested population included:small bowel stricture in 13 patients,small bowel dilation above ileal stricture in 10 patients,abdominal abscesses in 2 patients,enteric fistulae in 5 patients,lymphnodes enlargement(> 1 cm) in 7 patients and mesenteric enlargement in 9 patients.In order to compare findings by using SICUS,CTE,histology and surgery,characteristics of the small bowel lesions observed in CD each patient were blindly reported in the same form by one gastroenterologistsonologist,radiologist,surgeon and anatomopathologist.At surgery,lesions related to CD were detected in the distal ileum in all 13 patients,also visualized by both SICUS and CTE in all 13 patients.Ileal lesions > 10 cm length were detected at surgery in all the 13 CD patients,confirmed by SICUS and CTE in the same 12 out of the 13 patients.When using surgical findings as a gold standard,SICUS and CTE showed the exactly same sensitivity,specificity and accuracy for detecting the presence of small bowel fistulae(accuracy 77% for both) and abscesses(accuracy 85% for both).In the tested CD population,SICUS and CTE were also quite comparable in terms of accuracy for detecting the presence of small bowel strictures(92% vs 100%),small bowel fistulae(77% for both) and small bowel dilation(85% vs 82%).CONCLUSION:In our study population,CTE and the non-invasive and radiation-free SICUS showed a comparable high accuracy for assessing small bowel lesions in CD.

Small bowel adenocarcinoma in neoterminal ileum in setting of stricturing Crohn’s disease:A case report and review of literature

BACKGROUND Small bowel adenocarcinomas(SBA) are rare malignancies with exceedingly low survival rates, with different presentation in Crohn’s disease(CD). CD-induced SBA poses diagnostic challenges given overlapping presentation with stricturing CD and lack of diagnostics for early detection. Moreover, guidance is lacking on the impact of recently approved therapeutics in CD on SBA management. Here, we aim to highlight the future of CD-induced SBA management and discuss the potential merit of balloon enteroscopy and genetic testing for earlier detection.CASE SUMMARY We report the case of a 60-year-old female with longstanding Crohn’s ileitis, presenting with acute obstructive symptoms attributed to stricturing phenotype. Her obstructive symptoms were refractory to intravenous(Ⅳ) steroids, with further investigation via computed tomography enterography not providing additional diagnostic yield. Ultimately, surgical resection revealed SBA in the neoterminal ileum, with oncologic therapy plan created. However, this therapy plan could not be initiated due to continued obstructive symptoms attributed to active CD. Ultimately, infused biologic therapy was initiated, but her obstructive symptoms continued to remain dependent on Ⅳ corticosteroids. Review of diagnostics by a multidisciplinary care team suggested metastatic disease in the peritoneum, lending to a shift in the goals of care to comfort.CONCLUSION With the diagnostic and therapeutic challenges of concurrent SBA and CD, multidisciplinary care and algorithmic management can optimize outcomes.

Different roles of capsule endoscopy and double-balloon enteroscopy in obscure small intestinal diseases

AIM: To compare the roles of capsule endoscopy(CE)and double-balloon enteroscopy(DBE) in the diagnosis of obscure small bowel diseases.METHODS: From June 2009 to December 2014, 88 patients were included in this study; the patients had undergone gastroscopy, colonoscopy, radiological small intestinal barium meal, abdominal computed tomography or magnetic resonance imaging scan and mesenteric angiography, but their diagnoses were still unclear. The patients with gastrointestinal obstructions,fistulas, strictures, or cardiac pacemakers, as well as pregnant women, and individuals who could not accept the capsule-retention or capsule-removal surgery were excluded. Patients with heart, lung and other vital organ failure diseases were also excluded. Everyone involved in this study had undergone CE and DBE. The results were divided into:(1) the definite diagnosis(the diagnosis was confirmed at least by one of the biopsy,surgery, pathology or the drug treatment effects with follow-up for at least 3 mo);(2) the possible diagnosis(a possible diagnosis was suggested by CE or DBE,but not confirmed by the biopsy, surgery or follow-up drug treatment effects); and(3) the unclear diagnosis(no exact causes were provided by CE and DBE for the disease). The detection rate and the diagnostic yield of the two methods were compared. The differencein the etiologies between CE and DBE was estimated,and the different possible etiologies caused by the age groups were also investigated.RESULTS: CE exhibited a better trend than DBE for diagnosing scattered small ulcers(P = 0.242, Fisher's test), and small vascular malformations(χ 2 = 1.810,P = 0.179, Pearson χ 2 test), but with no significant differences, possible due to few cases. However,DBE was better than CE for larger tumors(P =0.018, Fisher's test) and for diverticular lesions with bleeding ulcers(P = 0.005, Fisher's test). All three hemangioma cases diagnosed by DBE in this study(including sponge hemangioma, venous hemangioma,and hemangioma with hamartoma lesions) were all confirmed by biopsy. Two parasite cases were found by CE, but were negative by DBE. This study revealed no obvious differences in the detection rates(DR) of CE(60.0%, 53/88) and DBE(59.1%, 52/88). However,the etiological diagnostic yield(DY) difference was apparent. The CE diagnostic yield was 42.0%(37/88),and the DBE diagnostic yield was 51.1%(45/88).Furthermore, there were differences among the age groups(χ 2 = 22.146, P = 0.008, Kruskal Wallis Test). Small intestinal cancer(5/6 cases), vascular malformations(22/29 cases), and active bleeding(3/4cases) appeared more commonly in the patients over50 years old, but diverticula with bleeding ulcers were usually found in the 15-25-year group(4/7cases). The over-25-year group accounted for the stromal tumors(10/12 cases).CONCLUSION: CE and DBE each have their own advantages and disadvantages. The appropriate choice depends on the patient's age, tolerance, and clinical manifestations. Sometimes CE followed by DBE is necessary.

Controversies about the use of serological markers indiagnosis of in flammatory bowel disease

The serological markers are increasingly used in diagnosis of inflammatory bowel disease(IBD).D-lactate and diamine oxidase are new indicators that can be used to reveal the damage to intestinal mucosa and permeability alteration in IBD.Although the two biological markers seem more sensitive,recent clinical trials and animal experiments have shown controversies about the use of them in diagnosis of IBD.Therefore, these markers should be interpreted cautiously and further prospective studies are needed to establish their clinical role in diagnosis of IBD.

Artificial intelligence in small intestinal diseases:Application and prospects

The small intestine is located in the middle of the gastrointestinal tract,so small intestinal diseases are more difficult to diagnose than other gastrointestinal diseases.However,with the extensive application of artificial intelligence in the field of small intestinal diseases,with its efficient learning capacities and computational power,artificial intelligence plays an important role in the auxiliary diagnosis and prognosis prediction based on the capsule endoscopy and other examination methods,which improves the accuracy of diagnosis and prediction and reduces the workload of doctors.In this review,a comprehensive retrieval was performed on articles published up to October 2020 from PubMed and other databases.Thereby the application status of artificial intelligence in small intestinal diseases was systematically introduced,and the challenges and prospects in this field were also analyzed.

Adhesive small bowel adhesions obstruction: Evolutions in diagnosis, management and prevention

Intra-abdominal adhesions following abdominal surgery represent a major unsolved problem. They are the first cause of small bowel obstruction. Diagnosis is based on clinical evaluation, water-soluble contrast followthrough and computed tomography scan. For patients presenting no signs of strangulation, peritonitis or severe intestinal impairment there is good evidence to support non-operative management. Open surgery is the preferred method for the surgical treatment of adhesive small bowel obstruction, in case of suspected strangulation or after failed conservative management, but laparoscopy is gaining widespread acceptance especially in selected group of patients. "Good" surgical technique and anti-adhesive barriers are the main current concepts of adhesion prevention. We discuss current knowledge in modern diagnosis and evolving strategies for management and prevention that are leading to stratified care for patients.

Measurement of prostaglandin metabolites is useful in diagnosis of small bowel ulcerations

BACKGROUND We recently reported on a hereditary enteropathy associated with a gene encoding a prostaglandin transporter and referred to as chronic enteropathy associated with SLCO2 A1 gene(CEAS). Crohn's disease(CD) is a major differential diagnosis of CEAS, because these diseases share some clinical features. Therefore, there is a need to develop a convenient screening test to distinguish CEAS from CD.AIM To examine whether prostaglandin E major urinary metabolites(PGE-MUM) can serve as a biomarker to distinguish CEAS from CD.METHODS This was a transactional study of 20 patients with CEAS and 98 patients with CD.CEAS was diagnosed by the confirmation of homozygous or compound heterozygous mutation of SLCO2 A1. We measured the concentration of PGEMUM in spot urine by radioimmunoassay, and the concentration was compared between the two groups of patients. We also determined the optimal cut-off value of PGE-MUM to distinguish CEAS from CD by receiver operating characteristic(ROC) curve analysis.RESULTS Twenty Japanese patients with CEAS and 98 patients with CD were enrolled.PGE-MUM concentration in patients with CEAS was significantly higher than that in patients with CD(median 102.7 vs 27.9 μg/g × Cre, P < 0.0001). One log unit increase in PGE-MUM contributed to 7.3 increase in the likelihood for the diagnosis of CEAS [95% confidence interval(CI) 3.2-16.7]. A logistic regression analysis revealed that the association was significant even after adjusting confounding factors(adjusted odds ratio 29.6, 95%CI 4.7-185.7). ROC curve analysis revealed the optimal PGE-MUM cut-off value for the distinction of CEAS from CD to be 48.9 μg/g × Cre with 95.0% sensitivity and 79.6% specificity.CONCLUSION PGE-MUM measurement is a convenient, non-invasive and useful test for the distinction of CEAS from CD.

Capsule endoscopy and single-balloon enteroscopy in small bowel diseases: Competing or complementary?

AIM To evaluate diagnostic yields of capsule endoscopy(CE) and/or single-balloon enteroscopy(SBE) in patients with suspected small bowel diseases.METHODS Were trospectively analyzed 700 patients with suspected small bowel diseases from September 2010 to March 2016. CE, SBE, or SBE with prior CE was performed in 401, 353, and 47 patients, respectively. Data from clinical and endoscopy records were collected for analysis. Indications, procedure times, diagnostic yields, and complications were summarized and evaluated.RESULTS The overall diagnostic yield for the CE group was 57.6%. The diagnostic yield of CE in patients with obscure gastroin testinal bleeding(OGIB) was significantly greater than that in patients with no bleeding(70.5% vs 43.8%, P < 0.01). The overall diagnostic yield of SBE was 69.7%. There was no difference in the diagnostic yield of SBE between patients with OGIB and those with no bleeding(72.5% vs 68.9%, P = 0.534). Forty-seven patients underwent CE prior to SBE. Among them, the diagnostic yield of SBE with positive findings on prior CE was 93.3%. In addition, SBE detected two cases with superficial ulcer and erosive lesions in the small bowel, which were missed by CE. However, one case with lymphoma and two with Crohn's disease were not confirmed by SBE. The rate of capsule retention was 2.0%. There were no significant complications during or after SBE examinations.CONCLUSION SBE is a safe and effective technique for diagnosing small bowel diseases. SBE with prior CE seemed to improve the diagnostic yield of small bowel diseases.

The role of small vessel disease in development of Alzheimer's disease

Classically Alzheimer＇s disease and vascular dementia have been considered as two different entities, with their own clinical criteria, but relatively recent epidemiological and clinicopathological studies suggest an overlap between them sharing not only most of the risk factors and some clinical aspects but also pathophysiological mechanisms. Cerebrovascular lesions, especially small vessel disease （lacunar infarcts, white matter hyperintensities and microbleeds）, may magnify the effects of mild Alzheimer＇s disease pathology and promote the progression of cognitive decline and may also be a precursor of neuronal damage and dementia. ＂Vascular hypothesis＂ of Alzheimer＇s disease would open a window for new approaches and treatments.

Multifocal stenosing ulceration of the small intestine

Several reports have described an apparently uncommon clinicopathological disorder that is characterized by multifocal stenosing small-intestinal ulceration.Compared to Crohn's disease,the ulcers are not transmural and typically remain shallow,and involve only the mucosa and submucosa.The disorder seems to be localized in the jejunum and proximal ileum only,and not the distal ileum or colon.Only nonspecif ic inflammatory changes are present without giant cells or other typical features of granulomatous inflammation.Most patients present clinically with recurrent obstructive events that usually respond to steroids,surgical resection,or both.With the development of newer imaging modalities to visualize the small-intestinal mucosa,such as double-balloon enteroscopy,improved understanding of the long-term natural history of this apparently distinctive disorder should emerge.

Plasmablastic lymphoma of the small intestine:Case report and literature review

Plasmablastic lymphoma(PBL) is a rare aggressive B-cell lymphoproliferative disorder,which has been characterized by the World Health Organization as a new entity.Although PBL is most commonly seen in the oral cavity of human immunodeficiency virus(HIV)-positive patients,it can also be seen in extraoral sites in immunocompromised patients who are HIV-negative.Here we present a rare case of PBL of the small intestine in a 55-year-old HIV-negative male.Histopathological examination of the excisional lesion showed a large cell lymphoma with plasmacytic differentiation diffusely infiltrating the small intestine and involving the surrounding organs.The neoplastic cells were diffusely positive for CD79a,CD138 and CD10 and partly positive for CD38 and epithelial membrane antigen.Approximately 80% of the tumor cells were positive for Ki-67.A monoclonal rearrangement of the kappa light chain gene was demonstrated.The patient died approximately 1.5 mo after diagnosis in spite of receiving two courses of the CHOP chemotherapy regimen.In a review of the literature,this is the first case report of PBL with initial presentation in the small intestine without HIV and Epstein-Barr virus infection,and a history of hepatitis B virus infection and radiotherapy probably led to the iatrogenic immunocompromised state.